Air-pump.



A, S. COMSTOGK.

AIR PUMP.

APPLICATION FILED JAN. 23, 1908.

903,543. I Patented Nov. 10, 1908.

,al il if@ THE NoRms PETER c,

ALPHONSO S. COMSTOGK, OF EVANSTON, ILLINOIS.

AIR-PUMP.

Speccaton of Letters Patent.

Patented Nov. 10, 1908.

Application led January 23, 1908. Serial No. 412,271.

To all rwhom it may concern:

Be it known that I, ALri-roNso S. CoM- srooir, a citizen of the UnitedStates, and resident of Evanston, county of Cook, and State of Illinois,have invented certain new and useful Improvements in Air-Pumps, of whichthe following is a specification, and which are illustrated in theaccompanying drawings, forming a part thereof.

The invention relates to air pumps; and has for its object to simplifyand improve the construction and operation of such devices.

The invention is exemplified in the construction to be hereinafterdescribed, and which is illustrated in the accompanying drawings,wherein Figure 1 is a front elevation of an air pump embodying theimprovements provided by the invention; Fig. 2 is a detail sectionalview of the same taken on the line 2 2 of Fig. 1; and Fig. 3 is similarto Fig. 2 but illustrates a slightly modified form of construction.

As shown in the drawings, a supporting frame 10 is provided having atits base a suitable supporting flange or floor plate 11. At the atop ofthe standard bearings 12, 13, are provided for a driving shaft 14. Uponone end of the driving shaft a belt pulley 15 is mounted, and upon theother end of the shaft there is provided a crank disk 16.

A pumping cylinder 17 is provided. As shown this cylinder is verticallydisposed below the crank disk 16, and is carried by a shelf or ledge 18,formed upon one side of the standard 10 intermediate its ends andadapted to permit of convenient access to the head end of the pumpcylinder from below the shelf. Preferably the wall of the cylinder 17takes the form of a simple tube having a flanged base 19, and what maybe termed the cylinder head and valve chest of the pump are bothcomprised in an integral block 20, interposed between the shelf 18 andthe flanged base 19 of the cylinder wall. The cylinder 17, block 20 andshelf 18 are rigidly united, as by means of screw-bolts 21, 22, whichenter the block from the shelf and from the flanged base 19 of thecylinder wall, respectively.

A plunger 23 is mounted within the cylinder 17, and as shown isconnected by a pitman 24 with a crank pin 25, formed upon the crank disk16. The plunger 23 is caused to t tightly within the cylinder by meansof the usual packing rings 26 of spring metal.

Induction and eduction passages, designated 27 and 28, respectively, areprovided for the pump in the block 20. Preferably each of such passagesleads from the interior of the pump cylinder to a lateral opening, as29, 30, in the block 20,the wall of the passage 28, as shown, beingthreaded adjacent the opening 30 for the attachment of suitableconnections for leading away the fluid compressed by the pump.

A seat 31 for an inwardly-opening valve 32 is provided in the passage27. Preferably this valve-seat is formed directly in the wall of thepassage without the interposition of bushings heretofore employed, andit is desirably located at the mouth of the passage within the chamberof the pump cylinder for the purpose of reducing the clearance space ofthe pump. As shown the stem of the valve 32 extends through an aperture33 in the block 20, in front of the valve-seat 31, and through anopening 34 in the shelf 18 to a point below the shelf, where it is eX-posed and may be grasped by the hand to rotate the valve on its seatfrom time to time to assist in the removal of dirt from below the valve,which would otherwise prevent its closing.

As shown a tubular grip-piece 35 incloses the outer end of the valvestem and is secured thereto as by means of a Cotter pin 36. Thisgrip-piece conveniently serves to limit the movement of the valve byengaging the block 20 at the mouth 37 of the aperture 33, when the valveis raised. The aperture 33 serves as a guide or bearing for thevalvestem, which slides freely therein, the closing of the valve beingeffected, as shown, by gravity.

A seat 38 for an outwardly-opening valve is provided in the eductionpassage 28. This valve-seat is preferably also formed directly in thewall of the passage without the interposition of a bushing, and isdesirably located adjacent the inner end of the passage for the purposeof reducing the clearance space of the pump. A spring-closed valve 39cooperates with the valveseat 38. As shown this valve has a socket 40formed upon its back for receiving a pintle 41, which enters the passage28 from below the valve and serves as a guide therefor. Preferably thepintle 41 is formed upon the inner end of a screw-plug 42, whichnormally serves as a closure for an aperture 43 which leads into thepassage 28 from the lower face of the block 20, and through which thevalve 39 `may be removed when the screw-plug is withdrawn. The head ofthe screw-plug 42 is made of sufficient length to be convenientlyaccessible from the under side of the shelf 18, the opening 34 providedin the shelf for receiving the stem of the valve 32 being preferably ofsuliicient size to also receive this plug and to permit of free accessto both. A closing spring 44 reacts between the face of the screw-plug42'and the under side of the valve 39.

As shown in Figs. 1 and 2 of the drawings, and as so far described, thepump provided by the invention is adapted for the compression of air forany purpose, as for example the inflation of vehicle tires. The devicemay, however, be readily adapted for use as an exhaust pump. To this endmeans may be provided for preventing leakage about lthe stem of theinduction valve 32, as shown in Fig. 3 of the drawings. In this form ofconstruction there is preferably no lateral opening for the passage 27,and a nipple 45 enters the passage from below, preferably through theopening 34 provided in the shelf 18. The outer end of this nipple ismost conveniently threaded to provide means for attaching connections,not shown, leading from the part to be exhausted. The inner end of thenipple provides a guide, as indicated at 47, for the stem of the valve32, the end of the nipple about the valve stem being, however, Afreelyperforated, as indicated at 4S, to permit of the passage of air fromthel interior of the nipple to the chamber of` the pump cylinder. Inthis form of construction the movement yof the valve 32 is limited bymeans of a collar 49, mounted upon the lower end of the valve-stem forengaging the inner end of the nipple 45 when the valve is raised.

The lubrication of the pump will be preferably effected through anaperture 50 in the wall of the pump cylinder, and by means of theimproved form of construction shown, any excess of lubricant providedwill find its way out of the pumn cylinder through the passages 27, 28,without interfering with the operation of the valves therein.

As shown, apertures, as 51, are formed in the socket 40 provided uponthe back of the valve 39 adjacent its base, to prevent air or oilbecoming entrapped in the socket in front of the pintle 41 and therebyinterfering with the oper-ation of the valve. By mounting the pumpcylinder in the upright position shown, however, lubricant will beunlikely to accumulate upon the valves, vas it will flow by gravity downthe stem of the valve 32, or the wall of the socket 40 pro- .Vided Auponthe back of the valve 39.

porting standard, a crankshaft journaled` at the top of the standard, ashelf formed on the side of the 'standard andV integral therewith, acompression cylinder carried by the shelf and removable therefrom, an

integral cylinder head and valve chest interposed between the shelf andthe cylinder and having a laterally opening eduction passagecommunicating with the interior of the cylinder, a valve controlling thepassage removable from below the shelf, a plunger within the cylinderand connection between the plunger and a crank of the shaft..V

2. In an air pump, in combination, a supporting standard, a crank shaftjournaled at the top of the standard,"a shelf formed on the side of thestandard and integral therewith, a compression cylinder carried by theshelf and removable therefrom, an integral cylinder head and valve chestinterposed between the shelf and the cylinder and havinglaterally-opening induction and eduction passages communicating with theinterior of the cylinder, a valve controlling each of the passages thestem of the induction valve beingexposedbelow the shelf, a plungerwithin the cylinder and connection between the plunger and a crank ofthe shaft. i y Y 3. In an airrpump in combination, a supportingstandard, a crank shaft journaled at the top of the standard, a shelfformed on the side of the standard and integral therewith, a compressioncylinder carried by the shelf and removable therefrom, an integralcylinder head and valve chest interposed between the shelf and thecylinder and having laterallyopening induction and eduction passagescommunicating with the interior Vof the cylinder, a valve controllingeach of the passages, the eduction valve being removable from below theshelf and the stem of the induction valve being exposed below the shelf,a plunger within the cylinder and connection between the plunger and acrank of the shaft. Y

4. In an air pump, in combination, a supporting standard, .a crank shaftjournaled at the top of the standard, a 4shelf projecting laterally fromthe standard intermediate of its ends, `a compression cylinder carred bythe shelf and removable from the standard independently of the shelf, anntegral cylinder head and valve chest nterposed between the shelf andthe cylinder and having a laterally-opening eduoton passagecommunicating with the interior of the cylinder, a, valve controllingthe passage removable from below the shelf, a plnngell within thecylinder, and connection between the plunger and a Crank of the shaft.

ALPHONSO S. COMSTOCK. Vtnesses:

CHARLES B. GILLsoN, LOUIS K. GILLsoN.

